Cross linked acrylic fibers or films prepared by copolymerizing acryloni trile unsaturated monomer containing halogenated s triazinyl groups and protein

ABSTRACT

CROSS-LINKED ACRYLIC FIBERS OR FILMS WHICH ARE OF IMPROVED HOT WATER-RESISTANCE AND HAVE A SILKY HAND OR FEEL, ARE OBTAINED BY (I) PREPARING AN ACIDIC SOLUTION OF A COPOLYMER OBTAINED BY COPOLYMERIZING IN AN ACIDIC MEDIUM (A) A VINYL MONOMERIC MATERIAL CONSISTING MAINLY OF ACRYLONITRILE AND (B) A POLYMERIZABLE UNSATURATED MONOMER HAVING A HALOGENATED S-TRIAZINYL GROUP OR HALOGNEATED PYRIMIDINYL GROUP IN THE PRESENCE OF (C) A POLYMERIZABLE UNSATURATED MONOMER HAVING A GROUP CONTAINING ACTIVE HYDROGEN, A GROUP CAPABLE OF FROMING ACTIVE HYDROGEN, A PYRIDYL GROUP, A PYRAZINYL GROUP OR QUINOLYL GROUP, AND/ OR (D) PROTEIN, AND THEN (II) EXTRUDING A VERY STABLE ACIDIC SOLUTION OF THE RESULTING POLYMER INOT THE FORM OF FIBERS OR FILMS, AND THEN HEAT-TREATING. THE OBTAINED FIBERS, FOR EXAMPLE, ARE USEFUL IN MAKING WOVEN OR KNITTED FABRICS OF CORRESPONDINGLY SUPERIOR PROPERTIES.

Sept. 18, 1973 AKlRA YAMAMQTQ ErAL 3,759,849

CROSS-LINKED ACRYLIC FIBERS OR FILMS PREPARED BY COPOLYMERIZINGACRYLONITRICE, UNSATURATED MONOMER CONTAINING HALOGENATED S-TRIAZINYLGROUPS, AND PROTEIN Original Filed Aug. 19, 1968 Fig o ,20 40 so soELONGATION STRENGTH /d) ELONGATION ,Z)

-United States Patent 3,759,849 CROSS-LINKED ACRYLIC FIBERS 0R FILMSPRE- PARED BY COPOLYMERIZING ACRYLONI- TRILE, UNSATURATED MONOMERCONTAIN- ING HALOGENATED s-TRIAZINYL GROUPS, AND PROTEIN Akira Yamamoto,Kunio Nakaoji, Kunio Oohara, Zenj ro Momiyama, Heiichiro Murakami, andAkira Tomlta, Otsu, Japan, assignors to Toyo Boseki Kabushiki KaishaOriginal application Aug. 19, 1968, Ser. No. 753,515. Divided and thisapplication July 26, 1971, Ser. No. 166,313 Claims priority, applicationJapan, Sept. 2, 1967, 42/ 56,502; Dec. 22, 1967, 42/82,509

Int. Cl. C08f 15/40; C08h 7/00 U.S. Cl. 260-8 4 Claims ABSTRACT OF THEDISCLOSURE Cross-linked acrylic fibers or films which are of improvedhot water-resistance and have a silky hand or feel, are obtained by (i)preparing an acidic solution of a copolymer obtained by copolymerizingin an acidic medium (a) a vinyl monomeric material consisting mainly ofacrylonitrile and (b) a polymerizable unsaturated monomer having ahalogenated s-triazinyl group or halogenated pyrimidinyl group in thepresence of (c) a polymerizable unsaturated monomer having a groupcontaining active hydrogen, a group capable of forming active hydrogen,a pyridyl group, a pyrazinyl group or quinolyl group, and/ or (d)protein, and then (ii) extruding a very stable acidic solution of theresulting polymer into the form of fibers or films, and thenheat-treating. The obtained fibers, for example, are useful in makingwoven or knitted fabrics of correspondingly superior properties.

This application is a division of applicants copending application Ser.No. 753,515, filed Aug. 19, 1968 now U.S. Pat. 3,626,049.

This invention relates to improved acrylic fibers and films high in thehot water-resistance, and also to processes for producing the same.

Generally fibers of acrylonitrile polymers have the disadvantage thatthey are much lower in strength and dimensional stability under' heat,particularly in hot water than any other synthetic fibers. Theresearches so far made to modify acrylic fibers have been directedmostly to the improvement of the dyeability and prevention offibrillation by copolymerizing acrylonitrile with other monomer(s).Therefore, such modification has resulted in the reduction of themolecular chain orientation of the acrylic fibers and also in thedeterioration in the hot waterresistance of the fibers.

There has recently been an attempt to improve the hot water-resistanceof acrylic fibers by introducing a crosslinkage betwen the molecules ofacrylic fibers. For example, in U.S. Pat. No. 3,399,007, there isdisclosed a process wherein a cross-linkable monomer such asdivinylbenzene is copolymerized with acrylonitrile. However, most ofsuch cross-linkable comonomers have the disadvantage that thecross-linking reaction proceeds so quickly during the polymerizing stepand up to the fiber formation step, that the polymer solution forforming shaped articles increases in viscosity or gels and the shapingoperation becomes difficult.

An object of the present invention is to provide fibers and films ofnovel cross-linked acrylonitrile copolymers high in hot water-resistanceand a process for producing the same.

A further object of the present invention is to provide improvedprotein-acrylonitrile graft copolymer fibers and films having a silkyhand or feel and high in hot waterresistance.

3,759,849 Patented Sept. 18, 1973 A still further object of the presentinvention is to provide a very stable solution for forming cross-linkedacrylic fibers or films.

Other objects of the present invention will become clear from thefollowing descriptions which will be made partly by referring to theaccompanying drawings wherein:

FIG. 1 is a graph showing the relation between the elongation and thestrength of fibers of this invention as compared with conventionalfibers, and

FIG. 2 is a graph similar to FIG. 1 but showing the same relation inrespect of other fibers of this invention as compared with theconventional fibers.

These objects of the present invention may be accomplished by preparingan acidic solution of a copolymer obtained by copolymerizing in anacidic medium (a) a vinyl monomeric material consisting mainly ofacrylonitrile and (b) a polymerizable unsaturated monomer having ahalogenated s-triazinyl group or halogenated pyrimidimyl group in thepresence of (c) a polymerizable unsaturated monomer having a groupcontaining active hydrogen, a group capable of forming active hydrogen,a pyridyl group, a pyrazinyl group or quinolyl group, and/ or (d)protein, and then extruding an acidic solution of the resulting polymerin the form of fibers or films, and then heat-treating.

The vinyl monomeric material consisting mainly of acrylonitrile in thepresent invention includes acrylonitrile alone or a mixture ofacrylonitrile and vinyl monomer(s) copolymerizable with acrylonitrile.Said vinyl monomers are, of course, other than those of the (b) and (c)monomers. In a monomeric mixture, acrylonitrile must be com tained in anamount of at least 70% by weight.

Examples of vinyl monomers are acrylic acid and methacrylic, theiresters such as methyl acrylate, methyl methacrylate and ethylacrylate,their amide derivatives such as acrylamide and methacrylamide,methacrylonitrile, allyl chloride, allyl sulfonic acid and its salts,ethylene sulfonic acid and its salts, itaconic acid and its esterderivatives, fumaronitrile, vinyl ethers such as methyl vinyl ether andethyl vinyl ether, methyl vinyl ketone, styrene, a-substituted styrenessuch as a-methyl styrene, nuclus-substituted styrenes such as 0-, morp-meth yl styrene, styrene sulfonic acid and its salts, vinyl esterssuch as vinyl chloride and v nyl acetate, vinyl lactams such as vinylcaprolactam and vinyl pyrrolidone and vinyl imidazole.

The halogenated s-triazinyl group or halogenated pyrimidinyl group inthe polymerizable unsaturated monomer (hereinafter referred to asmonomer A) having a halogenated s-triazinyl group or halogenatedpyrimidinyl group is of the following structure:

halogenated s-triazlnyl group 1 N l N halogenated pyrlmldinyl group l Ng},

Examples of preferable monomers A are of the following structuralformulas:

Z-allylamino-4,6-dichloro-s-triazine,

l CHz=CHCHgO- \N Z-amino-4-allyloxy-6-chloro-s-triazine,

X! R N l on =CHI!I \N 2- (p-vinylanilino) -4,6-dichloro-s-triazine,

2-acryloyloxyethylene amino-4,6-dichloro-s-triazine,

2-vinyloxyethylene amino-4,6-dichloro-s-triazine,

and, 2-(p-vinylphenoxy)-4,6-dichloro-s-triazine.

In the above formulas, R represents hydrogen or an alkyl group.

Further, those compounds in which the halogenated striazinyl group inthe above mentioned compounds substituted with a halogenated pyrimidinylgroup may also be used. Further, it is preferable that both X and X inthe monomer A are halogens. Particularly, among the halogens, chlorineis preferable.

The most preferable examples of the monomer A are2-allylamino-4,6-dichloro-s-triazine, 2-amino-4-allyloxy-6-chloro-s-triazine, 2- (p-vinylanilino)-4,6-dichloropyrimidine and2-allylamino-4,6-dichloropyrirnidine.

It is preferable that the content of the monomer A in the resultingacrylic copolymer is 0.03 to 10% by weight, and more preferably 0.3 toby weight. In case the content of the monomer A component is lower thanthe above mentioned range, the hot water-resistance of the obtainedfibers and films can not be improved to a desirable degree. On thecontrary, in case it is higher than the above mentioned range, theelongation and softness properties in the dry state of the thus obtainedfibers and films are reduced.

Preferable examples of the polymerizable unsaturated monomer(hereinafter referred to as monomer B) having a group containing activehydrogen, a group capable of forming active hydrogen, a pyridyl group, apyrazinyl group or a quinolyl group are as follows:

Allylarnine CHz=CHCHnNH5 Methallylamine CH2=C(CH3)CHqNHgAllylmethylamme" OH=OHCHNHCH3 Allylethylamine CH1=CHCH2NHCH2CH3acrylate. 5-(N-ethylamlno)ethyl CH =CHCOOCH2CH2NH CHjCHl CHz=C(CH3)OOOCH2CHINHCH| methylacrylate. fl-(N-ethylamino)ethyl methacrylate.

p-Amlnostyreno CH1=C H-NH= 2,3-dihydroxypropyl OH =C(CHCOOCH:CH(0H)OH1OH rnethacrylate.

Ethylene gllycol monovlnyl CH=CHO CHBOHEOH vmyl et Diethylene glycolmono- CH =CHO CHgCHzQ CHzCHgOH vinyl ether.

l-o-methacryloyl-D-glucose CHzCH O CH:

3-0-methacryloyl-D-glucose 6-0-methacryloyl-D-glucose1-o-methacryloyl-D-galactose 6-o-methacryloyl-D-galactose OH H H l H HOH 2-N-methacryloyl glucosamine CHrOH H on l-o-p-vinylphenyl glucoseCHzOH H l H --CH=CI-I2 OH H CH\ 1 H OH p-hydroxystyrene orn=on--on Vinylpyridine 2-methyl-5-vinyl pyridine 2-vinyl quinoline Vinyl pyrazine Ofcourse, the monomers B are not limited to the above exemplifiedparticular compounds but may be any of polymerizable unsaturatedmonomers having in the molecule a group containing active hydrogen suchas an amino group, imino group or hydroxyl group, a group (e.g. epoxygroup). capable of forming active hydrogen, a pyridyl group, a pyrazinylgroup or a quinolyl group.

Particularly preferable among the monomers B are allylamine, allylalcohol and vinyl pyridine.

It is preferable that the content of the monomer B in the resultingacrylic copolymer is 0.3 to 10% by weight, and more preferably 0.5 to 5%by weight. In case the content of the monomer B component is lower thanthe above mentioned range, the hot water-resistance of the obtainedfibers and films can not be improved to any desired degree. 0n thecontrary, in case it is higher than the above mentioned range, theelongation in the dry state of the obtained fibers and films is reducedand the materials lose their softness.

In regard to the protein to be used in the present invention,particularly preferable are natural proteins such as cow milk casein,yeast protein, gelatin, corn protein and soybean protein. In addition,there can be used modified proteins such as cyanoethylated protein andcarbamylethylated protein, or synthetic proteins.

It is preferable that the content of the protein in the resultingacrylic copolymer is 5 to 50%, more preferably 2040% by weight. In casethe content of the protein is lower than the above mentioned range,fibers high in the hot water-resistance and dyeability and having asilky hand and films high in the dyeability can not be obtained. On thecontrary, in case it is higher than the above mentioned range, thetoughness of the obtained fibers and films reduces.

In carrying out the polymerization it is preferable to use an acidicmedium of a pH of 6 or less, preferably a pH of 4 or less.

In case the polymerization is conducted in an acidic medium,substantially no cross-linking reaction proceeds during thepolymerization reaction and therefore a polymer solution stable in theviscosity is obtained. On the other hand, in case the polymerization isconducted in a neutral or alkaline medium, a cross-linking reactionquickly proceeds simultaneously with the polymerization reaction and theviscosity of the polymerization system increases so that the system gelsand becomes unuseful as a solution for forming fibers and films in somecases. It is therefore recommended to conduct the polymerization in anacidic medium. Thus, in the present invention, it is most preferable touse such medium showing itself an acidity as, for example, aconcentrated aqueous solution of zinc chloride. However, any mediumwhich is inherently neutral or basic can be also used by adjusting thepH to be m the acidic range by adding an acid.

Preferable media which can be used in the polymerization of the presentinvention are, for example, a concentrated aqueous solution of zincchloride, aqueous solution of nitric acid, an aqueous solution ofnitrate-containing nitric acid, an aqueous solution of perchloric acid,an aqueous soluton of a thiocyanate adjusted to be acidic, dimethylsulfoxide adjusted to be acidic, ethylene carbonate or an aqueoussolution of ethylene carbonate adjusted to be acidic, an aqueoussolution of formic acid, a concentrated aqueous solution of ureaadjusted to be acidic, an aqueous system adjusted to be acidic, and amixture of any two or more of the above mentioned media.

Except above, such other polymerization conditions as the monomerconcentration, catalyst, temperature and time may be those known per sein the art of polymerization or copolymerization, depending upon theparticular medium. In this connection, reference may be made, forexample, to Us. Pat. No. 3,104,154.

Typical examples wherein the polymerization is conducted in aconcentrated aqueous solution of zinc chloride and dimethyl sulfoxideshall be described as follows. It is preferable that the concentratedaqueous solution contains 40% by weight to the saturation of zincchloride. If a second such substance as sodium chloride is to be addedto the solution, the amount of such second substance is preferably inthe range of 0 to 20% by Weight.

The total concentration of the vinyl monomeric material, monomer Aprotein and/or monomer B to be added and dissolved into saidconcentrated aqueous solution of zinc chloride is preferably 3 to 40% byweight.

In case the monomer B contains an amino group, imino group, pyridylgroup, pyrazinyl group or quinolyl group, it is preferable that saidmonomer B is added in the form of a hydrochloride.

For the polymerization catalyst may be used known radical polymerizationinitiators soluble in the concentrated aqueous solution of zincchloride, such as azobisisobutylonitrile, ammonium persulfate, potassiumpersulfate or hydrogen peroxide. The catalyst may also be a redoxcatalyst system in which is simultaneously used such reducing agents assodium sulfite, acidic sodium sulfite, sodium thiosulfate or a ferroussalt. Further, the polymerization may also be conducted under theirradiation of radioactive rays such as, for example, gamma rays of Coor a light irradiation.

The polymerization temperature is to 60 C. The p0- lymerization time maybe less than 40 hours.

In case dimethyl sulfoxide is used as a medium, it should be adjusted tobe acidic by adding an organic acid or inorganic acid before initiatingthe polymerization. Preferably, the amount of the acid to be added isless than 10% by weight of the dimethyl sulfoxide. The vinyl monomericmaterial and protein and/or monomer B and/or protein may be added anddissolved before the dimethyl sulfoxide is adjusted to be acidic but itis preferable, in preventing the gelling of the polymerization system,to add the monomer A after the dimethyl sulfoxide has been adjusted tobe acidic. It is necessary that soybean protein which is hardly solublein dimethyl sulfoxide at the normal temperature should be dissolved atan elevated temperature such as 100 to 150 C. -It is preferable that thetotal concentration of the vinyl monomer material, monomer A and proteinand/or monomer B be 3 to 40% by weight on the dimethyl sulfoxide. Forthe polymerizing catalyst may be used radical polymerization initiatorssoluble in dimethyl sulfoxide, such as azobisbutylonitrile or ammoniumpersulfate. Further, it may be a redox polymerization in which a properreducing agent is simultaneously used. Further, it is also possible toconduct the polymerization with such radioactive rays as, for example,gamma rays of Co or a light-irradiation. The polymerization temperatureis 0 to 100 C. and the polymerization time may be less than 50 hours.

The acrylic polymer solution obtained by the polymerization in a properacidic medium, as mentioned above can be used for forming fibers andfilms. It is also possible to pour the solution into a nonsolvent forsaid polymer so that the polymer is precipitated and separated, washed,dehydrated and then dissolved into a proper acidic solvent such as, forexample, a concentrated aqueous solution of zinc chloride, dimethylsulfoxide adjusted to be acidic, dimethyl formamide adjusted to beacidic or concentrated nitric acid. In the latter case, it is preferableot use washing water which has been adjusted to be acidic and at acomparatively low temperature, preferably below 30 C. In such case, thewashed and dehydrated polymer can be stably stored as it is in a wetstate for a considerably long time.

The acidic polymer solution is then extruded in the form of filament orfilm into an acidic or neutral coagulating bath or into a hot gaseousatmosphere such as hot air.

Fibers and films can be formed from the polymer solution by any wellknown method. For example, in the case of forming fibers by wet-spinningmethod from the concentrated aqueous solution of zinc chloride of theacrylic polymer, the spinning solution is first filtered and deaeratedand is then extruded through a spinnerette into an aqueous solution of 5to 33% by weight of zinc chloride so as to coagulate the extrudedfilaments. The filaments are then water-washed to remove zinc chlorideand other materials deposited on them, are then stretched in a wetheated medium such as steam, hot water or a hot bath containing suchsalt as, for example, sodium sulfate and are dried and wound up.

In case an acidic dimethyl sulfoxide solution of the polymer is to beused as a spinning solution, there can be used a neutral dimethylsulfoxide-water mixed solution or n-butanol for the coagulating bath. Itis desirable to add an [acid to such coagulating bath so as to beacidic.

In the case of forming a film, the acidic polymer solution is extrudedin the form of a film into an acidic or neutral coagulating bath or intoa hot atmosphere through a slit instead of the spinnerette and the filmis washed with water and thermally stretched.

The filaments or films extruded into the acidic or neutral coagulatingbath or into a hot atmosphere contain an acidic substance having comefrom the original acidic polymer solution and/or the acidic coagulatingbath. After the formation of the fibers (filaments) or films,cross-linking reaction proceeds when the acidic substance is removede.g. by washing. The inter-molecular cross-linking proceeds slowly atthe room or normal temperature, but proceeds rapidly at a highertemperature such as 50 C. or higher, particularly at C. or higher.

It is preferable to stretch the formed fibers or films in order toimprove the mechanical properties. However, it is difiicult to effectthe stretching after the cross-linking has considerably proceeded.Therefore, in this invention, it is preferable that the stretching isconducted while the cross-linking has not yet proceeded or has proceededonly to a very small extent, and that the cross-linking is substantiallyproceeded during or after the stretching. Thus, for example, the formedfilaments or films are stretched before the above mentioned acidicsubstance thereon is removed or while the said acidic substance is beingremoved. Alternatively, the acidic substance is first removed, andimmediately thereafter or after travelling in an air of the normaltemperature for a very short period of time, the filaments or films arestretched. In order to complete the inter-molecular cross-linkingreaction, it is preferable to heat the filaments or films, during orafter the stretching, to a temperature of from 50 C. up to the meltingpoint. It is most preferable to first remove the acidic substance bywashing, and immediately thereafter or after travelling in an air of thenormal or room temperature for a short period of time, to conductstretching in a heated steam, hot water or hot bath containing salt(s)such as sodium sulfate.

The reason why the acrylic fibers or films produced by the presentinvention show an excellent hot waterresistance is that anintermolecular cross-linkage is formed due to the reaction of thehalogenated s-triazinyl group or halogenated pyrimidinyl group in theshaped article with the active hydrogen-containing group in the proteinand/ or the group containing active hydrogen, group capable of formingactive hydrogen, pyridyl group, pyrazinyl group or quinolyl group in themonomer B, within the fibers or films. Further, in the presentinvention, the halogeno-s-triazinyl group or halogenopyrimidinyl groupin the monomer A component shows no reactivity in an acidic medium sothat the cross-linking reaction does not sub stantially proceed duringthe polymerizing reaction and up to the formation of the fibers orfilms. Therefore, the viscosity of the polymer solution is very stablefor a long time.

Once such inter-molecular cross-linkage has been formed in the fibersand films, they do not dissolve again into the original solvent.

As compared with conventional acrylic fibers and films, the fibers andfilms produced by the present invention are higher in the strength whendry and wet, and are remarkably superior particularly in such propertiesas the strength and elongation in hot water. Therefore, the fibersproduced by the present invention, or their woven and knitted fabrics,and the films produced by the present invention are very high in thedimensional stability in a wet hot processing step such as dyeing.Particularly the proteinacrylonitrile graft-copolymer fibers produced bythe present invention have a silky luster and a soft elegant peculiarhand.

The present invention will be explained in more detail by the followingexamples wherein all parts and percentages are by weight unlessotherwise specified.

EXAMPLE 1 Fifty parts of cow milk protein were dissolved in 1940 partsof an aqueous solution of 60% zinc chloride. To

this solution were added 123.75 parts of acrylonitrile (hereinafterreferred to as AN) and 1.25 parts (corresponding to 1.0% on the totalamount of the monomers) of 2-allylamino-4,6-dichloro-s-triazine(referred to as AAT). While the solution was kept at a temperature of 10C. and was being slowly stirred, 125 parts of an aqueous solution of 60%zinc chloride containing 1.0% ammonium persulfate and 250 parts of anaqueous solution of 60% zinc chloride containing 1.0% sodium sulfitewere added to the solution. The polymerization was conducted understirring at 10 C. for 2 hours. The viscosity of the resulting polymersolution was 250 poises at 30 C. The polymerization conversion rate was48.8% (No. 1).

The same procedures were repeated except that AAT was added in an amountof 3.0% on the total amount of the monomers (No. 2) and that AAT was notadded (No. 3).

Each of the polymer solutions thus obtained was filtered and deaerated,and then extruded through a spinnerette into an aqueous solution of 28%zinc chloride kept at 2 to C. The formed coagulated filments were washedwith water and stretched 15 times the length in steam at 120 C. toobtain fibers of a silky luster. The properties, dry and wet, of thefibers are shown in Table 1. Their load-elongation curves in hot Waterat 90 C. are shown in FIG. 1.

TABLE 1 Dry state Wet state Initial modulus of elasticity (grams/denier) Initial modulusof elasticity Strength (grams/ (grams/ denier)denier) Elongation (P cent) Elongation (P cent) Strength,

grams denier) EXAMPLE 2 Fifty parts of gelatin were dissolved in 2000parts of a 60% aqueous solution of zinc chloride. To this solution wereadded 115 parts of AN, 6 parts of methyl methacrylate and 3.75 parts of2-(p-vinyl anilino)-4,6-dichloropyrimidine, (referred to as VAP). Thenthe solution was irradiated with gamma rays of 100 curies of C0 at anintensity of 1.0 10 r./hr. at 30 C. for 3 hours to effect thepolymerization. There was obtained a polymer solution (No. 4) with a.polymerization conversion rate of 99.3% and a viscosity of 290 poises at30 C.

The same procedure was repeated except that VAP was not added to obtaina polymer solution (No. 5).

Each of the polymer solutions was formed into filaments which werestretched under the same conditions as in Example 1 to obtain fibershaving a silky luster. The properties of the fibers thus obtained areshown in Table 2.

TABLE 2 Wet state Elongation (p cent) Dry state Elongation (P cent) Inhot water at 90 C Elongation (p cent) Strength (grams/ denier) Strength(e a s/ denier) l 0 As evident from Table 2, as compared with thecontrol fibers (No. 5 the fibers (No. 4) of the present invention werehigher in the strength both in dry and wet state and were remarkablysuperior particularly in the strength and elongation and in thedimensional stability in hot water.

EXAMPLE 3 Fifty parts of soybean protein were dissolved in 1940 parts ofan aqueous solution containing 55% zinc chloride and 5% sodium chloride.To this solution were added parts of AN, 6.25 parts of acrylamide(referred to as AAM hereinafter) and 3.75 parts of2-arnino-4-allyloxyfi-chloro-s-triazine (hereinafter referred to asAAOT). While the solution was kept at 8 C. and slowly stirred, parts ofan aqueous solution of 60% zinc chloride containing 1.0% ammoniumpersulfate and 250 parts of an aqueous solution of 60% zinc chloridecontaining 1.0% sodium sulfite were added to the solution and thepolymerization was proceeded under stirring for 3 hours to obtain apolymer solution (No. 6) of a polymerization conversion rate of 96 .5%and a viscosity of 215 poises at 30 C.

The same procedure was repeated except that AAOT was not added to obtaina polymer solution (No. 7).

Each of these polymer solutions was extruded through a spinnerette intoan aqueous coagulating bath containing 21% zinc chloride and 7% sodiumchloride. The formed filaments were treated in the same manner as inExample 1 to obtain fibers having a silky luster. The properties of thefibers thus obtained are shown in Table 3.

TABLE 3 Dry state Wet state In hot water at 90 C.

Elon- Elon- Elon- Strength gation Strength gation Strength gation n (13%ms/ ip r- (g l (p No. denier) cent) denier) cent) denier) cent) Asevident from Table 3, as compared with the control fibers (No. 7), thefibers (No. 6) of the invention were higher in the strength both in dryand wet, and were remarkably superior particularly in strength andelongation in hot water at 90 C.

EXAMPLE 4- Twenty two and a half parts of dried cow milk protein wereadded and dissolved into 277.5 parts of anhydrous dimethyl sulfoxide. Asmall amount of acetic acid was added to the solution to adjust the pHto about 3.5. Then 49.5 parts of AN, 0.5 part of AAT (corresponding to1.0% on the total weight of the monomers) and 0.75 part of ammoniumpersulfate were added to the solution. The polymerization was conductedat 30 C. under a reduced pressure for 12 hours to obtain a polymersolution (No. 8) of a polymerization conversion rate of 94.8%.

The same procedures were repeated except that AAT was added in an amountof 3.0% on the total weight of the monomers (No. 9) and that, as acontrol, no AAT was added (No. 10).

Each of the three polymer solutions thus obtained was extruded through aspinnerette into an aqueous solution of 50% dimethyl sulfoxide of a pHadjusted to 3.51 with acetic acid. The formed filaments were well washedwith water and were stretched 13 times the length in hot water 1 1 at 90C. to obtain white fibers of a silky luster. The prop erties of thefibers are shown in Table 4.

12 Each of these two polymer solutions was formed into fibers under thesame conditions as in Example 4 to obtain TAB LE 4 Dry state Wet stateIn hot water at 90 C.

Initial Initial modulus modulus of elas of elas- Strength ElonticityStrength Elonticity Strength Elon- (grams/ gation (grams/ (grams/ gation(grarns/ (grams/ gation N0. denier) (percent) denier) denier) (percent)denier) denier) (percent) As evident from Table 4, as compared with thecontrol fibers (No. 10), the fibers (Nos. 8 and 9) of the invention werehigher in the strength and initial modulus of elasticity both in dry andwet, and were remarkably superior particularly in strength andelongation in hot water at 90 C.

EXAMPLE 5 Twenty two and half parts of dried gelatin were dispersed andheated at 120 C. to be dissolved in 277.5 parts of anhydrous dimethylsulfoxide. A small amount of concentrated hydrochloric acid was added tothe solution to adjust the pH to about 3.0. To this solution were added47 parts of acrylonitrile, 1.5 parts of methyl methacrylate and 1.5parts of 2- (p-vinylanilino)-4,6-dichloro-pyrimidine (hereinafterreferred to as VAP). To this solution was further added 0.75 part ofazobisisobutylonitrile. The polymerization was conducted at 50 C. undera reduced pressure for 24 hours. The polymerization conversion rate inthis example was 93.4% (No. 11).

For comparison, the same procedure was repeated except that VAP was notadded to obtain a control polymer solution (No. 12).

Each of these polymer solutions was formed into filaments under the sameconditions as in Example 4 to ob tain fibers having a silky luster. Theproperties of the fibers thus obtained are shown in Table 5.

As evident from Table 5, as compared with the control fibers (No. 12),the fibers (No. 11) of the present invention were higher in the strengthboth in dry and wet state and were remarkably superior particularly inthe strength and elongation in hot Water at 90 C.

EXAMPLE 6 Twenty two and a half parts of dried soybean protein weredispersed and heated at 120 C. to dissolve in 277.5 parts of anhydrousdimethyl sulfoxide. Then formic acid was added to the solution to adjustthe pH to 3.0. To this solution were added 47 parts of acrylonitrile,1.5 parts of vinyl acetate and 1.5 parts of 2-amino-4-allyloxy-6-chloro-s-triazine (hereinafter referred to as AAOT). To this solutionwas further added 0.75 part of ammonium persulfate. The polymerizationwas conducted at C. under a reduced pressure for 18 hours. Thepolymerization conversion rate in this example was 96.8% (No. 13).

For comparison, the same procedure was repeated except that AAOT was notadded, to obtain a control polymer solution (No. 14).

fibers of a silky luster. The properties of the fibers thus obtained areshown in Table 6.

TABLE 6 Dry state Wet state In hot water at C.

Elon- Elon- Elon- Strength gation Strength gation Strength gation(grams! (p er- (grams/ (p er- (grams! (per- No. denier) cent) denier)cent) demer) cent) As evident from Table 6, as compared with the controlfibers (No. 14), the fibers (No. 13) of the present invention werehigher in the strength, lower in the elongation and higher in thedimensional stability particularly in hot water.

EXAMPLE 7 TAB LE 7 MA AAT AA. Total As evident from Table 7, the ratioof AN/MA in Nos. 1 to 4 was fixed at /5.

One hundred parts of the total monomers were added to 895 parts of anaqueous solution of 60% zinc chloride kept at 15 C. in cases of Nos. 15to 17 or 20 C. in case of No. 18. Then 135 parts of an aqueous solutionof zinc chloride containing 1.67% sodium sulfite and 80 parts of anaqueous solution of 60% zinc chloride containing 1.25% ammoniumpersulfate were added to the solution under stirring. Further, after 30minutes, 40 parts of the same aqueous solution of ammonium persulfateand zinc.

chloride were added thereto and the polymerization was conducted withstirring for 2 hours. The polymer solution was deaerated under a reducedpressure at 50 C. In any case the polymerization conversion rate was 99to 100%. The viscosity at 30 C. was 300 poises in Nos. 15, 17 and 18 and250 poises in No. 16.

TAB LE 8 Dry state Wet state Elon- Elon- Strength gation 7 Strengthgation ram (per- (grams! (perdenier) cent) denier) cent) As evident fromTable 8, as compared with the AN-MA copolymer fibers (No. 18), thecopolymer fibers (No. 18), the copolymer fibers (No. 17) in which AA wasadded but AATT was not added were lower in the strength and higher inthe elongation. On the other hand, due to the-intermolecularcross-linkage at the time of the thermostretching, the copolymer fibers(Nos. 15 and 16) of the present invention obtained by using both AA andAAT were higher in the strength, lower in the elongation and remarkablysuperior particularly in the strength and elongation in hot water at 90C. as compared with the control fibers of'No. 18.

Further, when the stretched filaments were dipped into an'aqueoussolution of 60% zinc chloride and an aqueous solution of 50% sodiumthiocyanate, the fibers Nos. 17 and, 18 were dissolved completely butthe fibers Nos. 15

and 16 were not substantially dissolved.

EXAMPLE 8 With the monomers in various proportions as in Table 9, thepolymerization was conducted in the same manner as in Example 7 in anaqueous solution of 60% zinc chloride at 15 C. The viscosity(centipoises at 30 C.) of the thus obtained polymer solution is alsogiven Table 9.

TABLE 9 Viscosity AA (AA Total of hydrooi monpolymer No.. AN AATchloride) omcrs solution Each of the polymer solutions was deaerated andthen extruded through a spinnerette into an aqueous solution of 28% zincchloride. The formed coagulated filaments were washed with water andthen stretched 12 times the length in boiling water and were then dried.The properties of the fibers thus obtained are shown in Table 10.

As evident from Table 10, as compared with the control fibers (No. 21),the fibers (Nos. 19 and 20) of the present invention were higher in thestrength and smaller in the elongation and were remarkably superiorparticularly in the strength and elongation in hot water at 90 C.

14 EXAMPLE 9 By using AN, MA, AAT and allyl alcohol (hereinafterreferred to as AOH) as monomers in various proportions, thepolymerization was conducted at a total monomer concentration of 8% byWeight in an aqueous solution of 60% zinc chloride at 15 C. Thepolymerizing catalyst and other polymerizing conditions were the same asin Example 7 (but the polymerizing temperature in No. 24 was 20 C.). Themonomer compositions, polymerization conversion rates (percent) and theviscosities (poises at 30 C.) of the polymer solution were as shown inTable 11.

then extruded through a spinnerette into an aqueous solution of 28% zincchloride. The formed filaments were washed with water, stretched 10times the length in a glycerin bath at 120 C. and were then dried. Theproperties of the fibers are shown in Table 12.

TABLE 12 Wet state Elongation (percent) Dry state In hot water at 0.

Strength (grams/ denier) Strength (grams! denier) Strength (grams/denier) cent) As evident from Table 12, as compared with the controlfibers (Nos. 23 and 24), the fibers (No. 22) of the present inventionwere superior particularly in the strength and elongation in hot waterat 90 C.

EXAMPLE 10 By using AN, MA, AAT and 4-vinyl pyridine (hereinafterreferred to as VP) as monomers in various proportions, thepolymerization was conducted at a total monomer concentration of 8% byweight in an aqueous solution of 60% zinc chloride at a polymerizingtemperature of 18 C. in case of No. 25 and at 20 C. in case of No. 26.The catalyst and other conditions were same as in Example 7. The monomercompositions and the viscosities (poises at 30 C.) of the polymersolutions were as shown in Table 13.

TABLE 13 Total of monomers Viscosity of polymer solution AAT (VP H01)Each of the polymer solutions was deaerated and was then extrudedthrough a spinnerette into an aqueous solution of 28% zinc chloride. Theformed filaments were washed with Water, then stretched 10 times thelength in a glycerin bath at 120 C. and were dried. The properties ofthe fibers thus obtained are shown in Table 14.

TABLE 14 Dry state Wet state In hot water at 90 C.

Elon- Elon- Elon- Strength gation Strength gation Strength gation(grams/ (per- (grams/ (per- (grams/ (per- No. denier) cent) denier)cent) denier) cent) As evident from Table 14, as compared with thecontrol fibers (No. 26), the fibers (No. 25) of the present inventionwere superior particularly in strength and elongation in hot water at 90C.

EXAMPLE 11 TABLE 15 Viscosity AA Total of of polymer No. AN MA AAP (AAH01) monomers solution Each of the polymer solutions was spun and thefilaments were stretched and dried in the same manner as in Example 7.The properties of the fibers are shown in Table 16.

TAB LE 16 Dry state Wet state In hot water at 90 0.

Elon- Elon- Elon- Strength gation Strength gation Strength gation(grams/ (p er- (grams/ (per- (grams/ (per- No. denier) cent) denier)cent) denier) cent) As evident from Table 16, as compared with thecontrol fibers (No. 28), the fibers (No. 27) of the present inventionwere superior particularly in the strength and elongation in hot waterat 90 C.

EXAMPLE 12 TAB LE 17 AA NO. AN AAM AAOT (AA H01) Tote.

The properties of the fibers obtained from the polymer solutions in thesame manner as in Example 9 are shown in Table 18.

TAB LE 18 Wet state Elongation (P cent) In hot water at C Elongationcent) Dry state Elongation (p cent) Strength (grams/ denier) Strength radenier) Strength (grams/ denier) As evident from Table 18, as comparedwith the control fibers (Nos. 30 and 31), the fibers (No. 29) of thepresent invention were superior particularly in the strength andelongation in hot water at 90 C.

EXAMPLE 13 TAB LE 19 AAT (AA HCl) Tote Thus, 100 parts of the totalmonomers (AA was added in the form of a hydrochloride) were added into1040 parts of deoxygenated water of a pH of 1.5 kept at 35 C. for No. 32and at 40 C. for No. 33. Then, 5.8 parts of an aqueous solution of 12%sodiumsulfite and 5.8 parts of an aqueous solution of 8% ammoniumpersulfate were further added thereto with stirring in a nitrogenatmosphere and the polymerization was conducted for 4 hours. The formedpolymer precipitate was separated, washed several times with 1 Nhydrochloric acid, and once with 'water and dehydrated with acentrifugal separator. The polymer (moisture content of 30%) wasdirectly added into a solvent consisting of 55% nitric acid, 20% zincnitrate and 25% water so as to produce a polymer concentration of 13% byweight. The mixture was stirred at 10 C. to disolve the polymer. Theresulting polymer solution was deaerated while being kept at 10 C. andwas extruded through a spinnerette into an aqueous solution of 35%nitric acid at 10 C. The formed coagulated filaments were washed withwater, stretched 7 times the length in boiling water and were dried. Theproperties of the obtained fibers are shown in Table 20.

TABLE 20 Wet state In hot water at 90 C v Elongation (p cent) Dry stateElongation cent) Strength (grams! denier) Strength (grarns/ denier)Strength (grams! denier) cent) As evident from Table 20, even in casethe polymerization was conducted in a nonuniform system, as compared 1 7EXAMPLE 14 With the same monomers as in Example 13, the polymerizationwas conducted at a total monomer concentration of about 20% by weight indimethyl sulfoxide at a temperature of 40 C. adjusted to a pH of 1.2with sulfuric acid.

Thus 100 parts of the total monomers were added to 395 parts of dimethylsulfoxide of a pH of 1.2. Further, 0.3 part of azobisisobutylonitrileand 0.1 to 0.3 part of dodecyl mercaptan were added thereto and thepolymerization was conducted with stirring at 45 C. for 40 hours in anitrogen atmosphere. The resulting polymer solution was deaeratedand'was then extruded through a spinnerette into an aqueous solution of82% dimethyl sulfoxide at 40 C. The formed coagulated filaments werestretched 7 times their length in a glycerin bath at 120 C., washed Wellwith Water, then passed as tensioned through a boiling water bath at 100C. and finally dried. The properties of the obtained fibers are shown inTable 21.

As evident from Table 21, as compared with the control fibers (No. 35),the fibers of the present invention were superior particularly in thestrength and elongation in hot water at 90 C.

EXAMPLE 15 By using AN, MA, MA, AAT and AA as monomers in variousproportions and using azoisobutylonitrile as a catalyst, thepolymerization was conducted at a total monomer concentration of 14.5%by weight in an aqueous solution of 94% ethylene carbonate in a nitrogenatmosphere at 50 C. for 20 hours. The resulting polymer solution was ofa viscosity of 705 poises at 50 C. and a polymer conversion rate of89.5% (No. 36).

For comparison, the same procedure was repeated eX- cept that AAT and AAwere not added to obtain a polymer solution (No. 37) of a viscosity of730 poises and a polymerization conversion rate of 88.0%.

Each of the polymer solutions was deaerated and was then extrudedthrough a spinnerette into an aqueous coagulating bath at 30 C.,adjusted to pH 1.8 with hydrochloric acid. The formed filaments werewater-washed then stretched 7 times their length in boiling water andwere dried. The monomer compositions employed are shown in Table 22 andthe properties of the obtained fibers are shown in Table 23.

As evident from Table 23, as compared with the control fibers (No. 37),the fibers (No. 36) of the present invention were remarkably superiorparticularly in the strength and elongation in hot water at 90 C.

18 EXAMPLE 16 TABLE 24 Wet state Dry state Elongation (p cent) In hotwater at C.

Elongation (p cent) Strength (grams/ denier) Strength (grams/ denier)Strength (gr ms/ denier) cent) As evident from Table 24, as comparedwith the control fibers (No. 39), the fibers (No. 38) of the presentinvention were remarkably superior particularly in the strength andelongation in hot Water at 90 C.

EXAMPLE 17 Four parts of soybean protein were dissolved in parts offormic acid. Then 15.5 parts of AN, 0.5 part of AAT and 0.6 part ofa,a-azoisobutylonitrile were added thereto and to the mixture waspolymerized at 60 C. under a reduced pressure for 6 hours (No. 40).Then, the resulting reaction mixture was put into 500 parts of water andwas dehydrated with a centrifugal separator to obtain 23.4 parts of ahydrous polymer of a moisture content of 30%. This hydrous polymer wasadded and dissolved with stirring into an aqueous solution of 60% zincchloride to obtain a solution of a polymer concentration of 8%. Thepolymer solution was filtered and deaerated and was then extrudedthrough a spinnerette into an aqueous solution of 28% zinc chloride at0%. The formed filaments were washed with water, then stretched 15 timestheir length in steam at 120 C. and were dried to obtain fibers having asilky luster.

The same procedure was repeated except that AAT was not added (No. 41).

The properties of the fibers thus obtained are shown in Table 25.

invention were remarkably superior particularly in their strength andelongation in hot water at 90 C.

EXAMPLE 1% Four parts of cow milk casein were dissolved in parts of anaqueous solution of 50% urea adjusted to a pH of 6.01 with hydrochloricacid. To this solution were added 15.5 parts of AN, 0.5 part of AAT and1 part of a,a-azoisobutylonitrile. The mixture was polymerized at 60 C.for 6 hours (No. 42). Then the polymer precipitate was centrifugallyseparated, washed with water adjusted to a pH of 6 and was dehydrated toobtain 21.7 parts of a hydrous polymer of a water content of 28%. Thehydrous polymer was processed in the same manner as in Example 17 toobtain fibers having a silky luster (No. 42).

19 For comparison, the same procedure was repeated except that AAT wasnot added (No. 43).

The properties of the fibers thus obtained are shown in Table 26.

As evident from Table 26, as compared with the conin Example 1 wasextruded through a slit 1.5 mm. wide and 1 m. long into an aqueoussolution of 35% zinc chloride at C. and was made to slide down, whilebeing slowly coagulated at a velocity of m./min., on a fiat plateinclined by degrees within coagulating bath. Then, the coagulated filmwas transferred to a water-washing bath, and was then stretched 5 timestheir length in one direction in hot water to obtain a stretchedtransparent film (No. 47).

In the same manner films were prepared from the polymer wherein theamount of AAT was 3.0% based from the polymer not containing AAT (No.49). on the total amount of the monomers (No. 48) and also The physicalproperties in the stretching direction of trol fibers (No. 43), thefibers (No. 42) of the present 15 th film r ho n in Tabl 28,

TAB LE 28 Dry state Wet state In hot water at 90 C.

Tensile Elon- Tensile Elong- Tensile Elon- Shn'nk strength gationstrength gation strength gation age No. (kg/111. (percent) (kg/m!)(percent) (kg/m2) (percent) (percent) invention were remarkably superiorparticularly in the strength and elongation in hot water at 90 C.

EXAMPLE 19 Five parts of corn protein were added to 80 parts of dimethylformamide adjusted to a pH 2.0 with phosphoric acid and were dissolvedtherein with stirring at the room temperature. Then, to this solutionwere added 14.85 parts of AN and 0.15 part of AAT and, as catalysts,0.005 part of cupric nitrate and 0.225 part of potassium persulfate. Themixture was polymerized with stirring in a nitrogen gas current for 5hours (No. 44). The polymerization conversion rate was 94.3%.

As evident from Table 28, as compared with the control film (No. 49),the films of the present invention (Nos. 47 and 48) were remarkablysuperior particularly in the strength, elongation and shrinkage in hotwater at 90 C.

EXAMPLE 21 Films were formed under the same conditions as in Example 20except that polymer solutions obtained in the same manner as in Example7 were used. The physical properties of the films in the stretchingdirection are shown in Table 29 wherein Nos. to 53 correspondrespectively to Nos. 15 to 18 in Table 7.

TABLE 29 Dry state Wet state In hot water at 90 C.

Tensile Elon- Tensile Elong- Tensile Elon- Shrinkstrength gationstrength gation strength gation age (kg/111. (percent) (kg/111.(percent) (kg/m1) (percent) (percent) The same procedure was repeatedexcept that AAT was added in an amount of 3.0% based on the totalmonomers (No. 45) and that no AAT was added (No. 46).

"Each of the three polymer solutions was extruded through a spinneretteinto a hot air spinning tube at 200 to 250 C. and the formed filamentswere taken at a velocity of 110 m./min. The filaments were thenstretched 5 times the length in hot water at 100 C. and were dried toobtain fibers having a silky luster. The properties of the fibers thusobtained are shown in Table 27.

TABLE 27 Dry state Wet state In hot water at 90 C Elon- Elon- Elon-Strength gation Strength gation Strength gation (grams/ (per- (grams/(per- (grams/ (per- No. denier) cent) denier) cent) denier) cent) Asevident from Table 27, as compared with the control fibers (N0. 46), thefibers (Nos. 44 and 45 of the present As evident from Table 29, ascompared with the con- 0 trol films (Nos. 52 and 53), the films of thepresent inand halogenated pyrimidinyl groups of the general formula:

invention were higher in the strength when dry and wet and remarkablysuperior particularly in the strength and elongation in hot water at 90C.

EXAMPLE 20 A polymer solution obtained in the same manner as whereineach of X and X is a halogen, hydrogen, alkyl group, amino group,hydroxyl group, mercapto group or carboxyl group and wherein at leastone of X and X must be a halogen, and (c) 550% by weight of a pro tein,said protein being cross-linked at its active hydrogencontaining groupwith the halogenated S-triazinyl group or halogenated pyrimidinyl group.

2. An acrylic fiber or film of a copolymer obtained by copolymerizing inan acidic medium (a) a vinyl monomeric material consisting mainly ofacrylonitrile, (b) 0.03 to by weight of a polymerizable unsaturatedmonomer having a group selected from the class consisting of halogenatedS-triazinyl groups of the general formula:

X1 N L \N if I and halogenated pyrimidinyl groups of the generalformula:

wherein each of X and X is a halogen, hydrogen, alkyl group, aminogroup, hydroxyl group, mercapto group or carboxyl group and wherein atleast one of X and X must be a halogen, (c) 5-50% by weight of a proteinand ((1) 03-10% by Weight of a polymerizable unsaturated monomercomponent having a group selected from the class consisting of amino,imino, hydroxyl, glycidyl, pyrazinyl and quinolyl groups, said proteinand monomer ((1) being cross-linked at its active hydrogen-containinggroup with the halogenated S-triazinyl group or halogenated pyrimidinylgroup.

3. An acrylic fiber or film according to claim 1 wherein thepolymerization components (a) to (c) are produced from an acidic mediumat a temperature of about 0 to about 100 C.

4. An acrylic fiber or film according to claim 2 wherein thepolymerization components (a) to (d) are produced from an acidic mediumat a temperature of about 0 to about 100 C.

References Cited UNITED STATES PATENTS 3,050,496 8/ 1962 DAlelio260-80-72 X 3,053,812 9/1962 DAlelio 260-80-72 X 3,153,015 10/1964DAlelio 260-80-72 X 3,154,523 10/ 1964 DAlelio 26080-72 X 3,271,4789/1966 DAlelio 260-80-72 X 3,213,053 10/1965 Kendrick 26029-6 RB3,511,822 5/1970 Kraft et a1 2608 UX 3,478,006 11/1969 Pilling 260-8553,104,154 9/1963 Morimoto et al. 260-8 X 30 HOWARD E. SCHAIN, PrimaryExaminer

